Not sure of the timeline on when to pick it up but I might throw in a suggestion to get as super familiar with the specific Rv you are getting BEFORE doing the pickup as that will let you know what and where to to look to check things are working as they should.
Many dealers do not know the unit when they show it to you and are way too prone to brushing off things not working as if that was normal. sometimes they don't know but others do cheat!
All Rv have some personal "quirks" in operation but how is your experience level with RV and motorhomes?
As a start, I think this will be the online owners manual for that unit and it will be super helpful if you look through it and spot any details you don' understand. One of the big flaws we see in shopping is not knowing what is expected and when the sales folks may be trying to blow their lack of knowledge as simply "normal".
https://www.winnebago.com/Files/File...7/07Voyage.pdf
If they can't get something to work, do not be too quick to accept the idea that the fault is the batteries are run down. Rundown batteries are often damaged batteries and that is not something you need to buy upfront.
If the slide won't go out, the steps won't come in or lots of those small points because they tell you it's normal for the batteries to be down, let them know you will come back when the batteries do hold a charge!
Knowledge is power so , study first and don't let their problems become your new problems.